thepamster
70cc twin V2
Biplanes Rule.
Sport PAU 27% Pitts Challenger Build/Review
- Thread starter Bartman
- Start date
Decal Dennis
TEAM EP&G
Awesome....can't wait to see it finished!
Bartman
Defender of the Noob!
Was waiting on a tailwheel for this. Sean Tucker's Challenger has a Haigh style tailwheel and his airplane is very low to the ground in the back as a result so I wanted to have that same posture for the PAU Challenger.
Ever wonder what a Haigh tail wheel is in the first place? Your standard tailwheel will turn along with the rudder through cables and springs like we're all pretty familiar with but a standard tail wheel will continue moving with the rudder throughout your takeoff so if things get squirrelly (how the hell do you spell squirrelly?) the tailwheel won't do much to help straighten things out. The Haigh tail wheel on the other hand is what is referred to as a locking tailwheel. See that little thing sticking up from the top of where the tail wheel is? That's a lever that is pulled from the cockpit via a cable to unlock the tailwheel. Some planes make it unlock when the control stick is back like when you're taxiing, some planes have a separate lever to unlock it. But when it's time for takeoff (and landing) the wheel is locked straight and it helps (some say) to keep the plane nice and straight on the runway. You'll still have rudder for directional control but that tailwheel being locked will help things from getting squirrelly (squirrely?). The Haigh tailwheel is lighter too using a tapered steel rod for the spring and a smaller/lighter wheel.
So to simulate the look of Sean Tucker's plane (the image above is probably a Challenger III or IV which is less a modified Pitts S2S and more of a fully custom airplane similar to a Pitts S2S) I bought an Ohio Superstars Haigh style tail wheel, size large. The steel rod extended back a little farther than I wanted it to so I cut the wire off at the bend, measured up an inch, rebent it using heat from a welding torch and then quenched it in water to put some spring back into it. It mounts to the plywood mounting plate that is there for the stock tailwheel spring so no further changes were required.
Mounting the main gear is easy as pie. The instructions say to use a soldering iron to burn open the holes where the bolts go for the main landing gear. I like to cut an x across the hole and let the bolt push the flaps of the covering into the holes. Four bolts later you've got the main gear mounted.
The wheel pants should be placed so that they are level when the airplane is level. The area in front of the cockpit is parallel to the roll axis or longitudinal axis of the plane so if you get the top of the fuselage (ahead of the cockpit) level then the wheel pants should be mounted to be level at that attitude as well. So up went the tail of the plane onto a cardboard box and a level was used to get the fuselage level.
Masking tape was used on the wheel pants to estimate a reference line front/back that could be compared to a level to get them just right. Two 4x40 bolts go through the gear legs, into a plywood reinforcing block in the wheel pants and are held there by blind nuts. It's never a bad idea with non-locking hardware to use some loctite on the threads to keep things secure just be careful there's no plastic around as Loctite will soften plastics and some composites.
With the main gear and tail wheel in place and the wheel pants mounted, the plane could be put on the bench for a nice glamour shot.
Ever wonder what a Haigh tail wheel is in the first place? Your standard tailwheel will turn along with the rudder through cables and springs like we're all pretty familiar with but a standard tail wheel will continue moving with the rudder throughout your takeoff so if things get squirrelly (how the hell do you spell squirrelly?) the tailwheel won't do much to help straighten things out. The Haigh tail wheel on the other hand is what is referred to as a locking tailwheel. See that little thing sticking up from the top of where the tail wheel is? That's a lever that is pulled from the cockpit via a cable to unlock the tailwheel. Some planes make it unlock when the control stick is back like when you're taxiing, some planes have a separate lever to unlock it. But when it's time for takeoff (and landing) the wheel is locked straight and it helps (some say) to keep the plane nice and straight on the runway. You'll still have rudder for directional control but that tailwheel being locked will help things from getting squirrelly (squirrely?). The Haigh tailwheel is lighter too using a tapered steel rod for the spring and a smaller/lighter wheel.
So to simulate the look of Sean Tucker's plane (the image above is probably a Challenger III or IV which is less a modified Pitts S2S and more of a fully custom airplane similar to a Pitts S2S) I bought an Ohio Superstars Haigh style tail wheel, size large. The steel rod extended back a little farther than I wanted it to so I cut the wire off at the bend, measured up an inch, rebent it using heat from a welding torch and then quenched it in water to put some spring back into it. It mounts to the plywood mounting plate that is there for the stock tailwheel spring so no further changes were required.
Mounting the main gear is easy as pie. The instructions say to use a soldering iron to burn open the holes where the bolts go for the main landing gear. I like to cut an x across the hole and let the bolt push the flaps of the covering into the holes. Four bolts later you've got the main gear mounted.
The wheel pants should be placed so that they are level when the airplane is level. The area in front of the cockpit is parallel to the roll axis or longitudinal axis of the plane so if you get the top of the fuselage (ahead of the cockpit) level then the wheel pants should be mounted to be level at that attitude as well. So up went the tail of the plane onto a cardboard box and a level was used to get the fuselage level.
Masking tape was used on the wheel pants to estimate a reference line front/back that could be compared to a level to get them just right. Two 4x40 bolts go through the gear legs, into a plywood reinforcing block in the wheel pants and are held there by blind nuts. It's never a bad idea with non-locking hardware to use some loctite on the threads to keep things secure just be careful there's no plastic around as Loctite will soften plastics and some composites.
With the main gear and tail wheel in place and the wheel pants mounted, the plane could be put on the bench for a nice glamour shot.
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Bartman
Defender of the Noob!
I was going to try to assemble a short history of the different Pitts Challengers that Sean Tucker has flown over the years but it's confusing to tell what happened and when. The red Oracle planes are either the III or IV and the IV may just be the III with the split ailerons of the new wings Steve Wolf built for it.
The II was the black 1-800-COLLECT plane.
There were a couple of crashes along the way, Sean Tucker crashed one when his control stick broke off in flight forcing him to bail out and there was mention somewhere of a ferry pilot crashing one of his planes as well.
I'll keep snooping around when I have time and get back to you guys on it!
Bart
The II was the black 1-800-COLLECT plane.
There were a couple of crashes along the way, Sean Tucker crashed one when his control stick broke off in flight forcing him to bail out and there was mention somewhere of a ferry pilot crashing one of his planes as well.
I'll keep snooping around when I have time and get back to you guys on it!
Bart
Attachments
Terryscustom
640cc Uber Pimp
So is it Seans red plane that has the split ailerons. I was always going to research how he uses that on the bipe but never got around to it.
Bartman
Defender of the Noob!
yes, i saw a reference to them that says the inboards have half the throw of the outboard ailerons. it's all mechanical and with weight being what it is for full scale planes (they don't have 2:1 or more power to weight rations like we do) i doubt there's anything other than aileron functions happening with those inboard aileron panels.
digital radios being what they are for us we can do all sorts of things with different panels on individual servos but not so with full scale (unless you're talking about a fly by wire jet like an F22 but that's another forum site for another time!)
Bart
digital radios being what they are for us we can do all sorts of things with different panels on individual servos but not so with full scale (unless you're talking about a fly by wire jet like an F22 but that's another forum site for another time!)
Bart
Terryscustom
640cc Uber Pimp
Cool, I really like the scale exhaust outlet area on the cowl and the vents in the side on the full scale. Now you got me thinking of getting one of these and recover it for the skip stewart scheme......love that plane for some reason. Too many projects cooking for right now though
Attachments
Bartman
Defender of the Noob!
that 2nd photo is probably the Challenger III with the single outboard ailerons, fwiw.
i don't see myself doing much more in the way of customizing things. it's funny how some people though pick up the finest scale details. i like the lines that PAU put into the plane and I'm really looking forward to flying it but i've just never been a hardcore scale guy for whatever reason. when i think about the time and effort that goes into making a world class scale RC plane I start having seizures!
although i would love to have servos just on the lower wing and slave struts to the upper ailerons....gotta admit i've been kicking around how i could do that. lol
i don't see myself doing much more in the way of customizing things. it's funny how some people though pick up the finest scale details. i like the lines that PAU put into the plane and I'm really looking forward to flying it but i've just never been a hardcore scale guy for whatever reason. when i think about the time and effort that goes into making a world class scale RC plane I start having seizures!
although i would love to have servos just on the lower wing and slave struts to the upper ailerons....gotta admit i've been kicking around how i could do that. lol
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Bartman
Defender of the Noob!
something like (6x32 size) this maybe
http://datasheets.globalspec.com/ps/6125/Festo/AF6A453A-3551-42D7-A9A5-69B5118F45F9
mounted on the top side of the lower aileron to the 6/32 control horn screw and then another on the bottom of the upper aileron. you'd need a streamline strut between the two ailerons but something could probably be found to work correctly.
hmmmmm.
http://datasheets.globalspec.com/ps/6125/Festo/AF6A453A-3551-42D7-A9A5-69B5118F45F9
mounted on the top side of the lower aileron to the 6/32 control horn screw and then another on the bottom of the upper aileron. you'd need a streamline strut between the two ailerons but something could probably be found to work correctly.
hmmmmm.